One vertex per element, one color per generator, with an edge from x to x·s.
(9,10)(11,16)(12,21)(13,17)(14,18)(15,20)(19,23)(22,24)(25,26,31,37)(27,38,41,33)(28,35,29,44)(30,36,32,47)(34,45,53,43)(39,49,42,54)(40,51,46,50)(48,56,52,55)(1,2)(3,7)(4,6)(5,8)(9,11)(10,15)(12,19)(13,22)(14,20)(16,18)(17,23)(21,24)(25,27,31,41)(26,33,37,38)(28,42,29,39)(30,46,32,40)(34,52,53,48)(35,49,44,54)(36,51,47,50)(43,55,45,56)(1,3)(2,5)(4,8)(6,7)(9,11)(10,16)(12,22)(13,19)(14,20)(15,18)(17,23)(21,24)(25,28,31,29)(26,34,37,53)(27,39,41,42)(30,43,32,45)(33,48,38,52)(35,36,44,47)(40,55,46,56)(49,50,54,51)(3,8)(5,7)(9,12,14,13)(10,17,18,21)(11,19,20,22)(15,23,16,24)(25,29,31,28)(26,35,37,44)(27,39,41,42)(30,43,32,45)(33,49,38,54)(34,36,53,47)(40,56,46,55)(48,50,52,51)(2,6)(5,7)(9,13,14,12)(10,17,18,21)(11,19,20,22)(15,24,16,23)(25,30,31,32)(26,36,37,47)(27,40,41,46)(28,43,29,45)(33,50,38,51)(34,44,53,35)(39,55,42,56)(48,54,52,49)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.